This paper describes the design of ultra wideband (UWB) pulse generator circuit. The design is based on source couple logic (SCL) for it's low power and high immune to noise. The design is simulated and result of the circuit is dual pulses with width around 200 p second, which used to encode the bipolar data using 2-input multiplexer. Mainly, in this paper, we concern about pulse generator circuit and data modulation. The result validate the design and we get the desired output. All simulation is carried out using cadence spectre EDA and using MIMOS 0.35 mum process PDK.